/*进入动画*/
.preCssAAA-enter {
  opacity: 0;
}
.preCssAAA-enter-active {
  opacity: 1;
  transition: opacity 2s ease;
}
/*离开动画*/
.preCssAAA-exit {
  opacity: 1;
}
.preCssAAA-exit-active {
  opacity: 0;
  transition: opacity 3s ease;
}
